1. Field of the Invention
The present invention relates to an automatic balancing apparatus that balances the rotation of an object to be handled and to a rotating apparatus, a disc drive apparatus, a balancer, and a housing mounted in the automatic balancing apparatus.
2. Description of the Related Art
When a disc as a record medium is rotated on a turntable of a disc apparatus such as an optical disc apparatus or a magnetic disc apparatus that records and/or reproduces for example data, the rotation of the disc may be unbalanced. As a result, the stability of recording and/or reproducing may decrease.
A technique of improving the balance of the rotation of a disc has been proposed for example in Japanese Patent Application Laid-Open No. HEI 4-312244, paragraph (0006), FIG. 1. In this related art reference, a disc-shaped member having a space portion that contains magnetic fluid that operates as a balancer is disposed such that the member is rotated together with a motor shaft. The disc-shaped member has a boss portion. A ring magnet is mounted on a side circumferential surface of the boss portion. Thus, when the rotation rate of the rotation shaft is low, the ring magnet attracts magnetic fluid such that the disc-shaped member is not unbalanced.